Hole cutting tool



j Patented Nov. 26, 19.46

anni

Lawson A. Smith, Los Angeles, Calif., assigner toRobertH.' Clark, LosAngeles', Calif.

Applicatie eur-ui l1 194,3 Sei-ellis- 49822.16

4.0mm. (c1. :fn-69.)

This invention relates totools and relates more particularly to tools for forming or cutting openings.Y A general ob'ject'of the invention uis'to provide a practical, effective tool of this character that is adjustableitorcut openings throughout a very Wide rang'e'of diameters. Another object ofthis'inve'ntionis to provide a tolff the character referred to in 'which the cuttingparts are easily ,and guickly adjusted simultaneously.

'Another cb ect of this invention is toprovide a :toolof vrthe character rf'aferred to in which the bitsorfcutting parts'arer 'adjusted uniformly or equally to' ir'sureaccurate tracking in -their engagement Withkthe'vvork; -The adjusting means 'of' thev tool of this invention is positiveand the cutting parts are shifted equal distances when the fadjustir'ig' means' is actuated.

' Another obje'ctof this invention is to provide aftocl of the vclfiaracter mentioned embodying simple, eifective means for releasably settingor 'lookinlgthe' parts in the selected adjusted positions. l

" fAnother object of the invention is `to provide y aftool of tlie'character mentionedzin which the cutting parts'are on the extreme .outer ends of thearmsA so that the'too-l. is capable of forming lepenings ator immediately adjacent a projection, shoulder orv other obstruction onthe vvork.

N vv'Another kobject of this invention is .to provide a 'hole-cutting tool of .the character referred toin which the cuttingparts are adjustably and replaceably secured inthe outer ends of the .arms by novel means Which do not necessitate projections on the outer ends of the arms.

A further object of this invention is to provide a tool of the character mentioned that is simple and inexpensive to manufacture and which embodies a minimum number of parts.

The various objects and features of my invention will be fully understood from the following detailed description of typical preferred form and application of the invention, throughout which description reference is made to the accompanying drawing, in Whichz.

Fig. 1 is a side elevation of a device embodying the invention. Fig. 2 is an enlarged fragmentary vertical detailed sectional view taken as indicated by line 2---2 on Fig. 1. Fig. 3 is a bottom view of the tool shown in Fig. 1. Fig. 4 is a horizontal detailed sectional view taken as indicated by line 4 4 on Fig. 1 with certain portions appearing in elevation, and Fig. 5 is a side view of the key for adjusting the tool.

The tool provided by my invention may be said to comprise, generally, a body 5d, a pair of arms 57i shiftably fearried by the body,k cutting parts 5 2 o n jthe'out'er ends ef the arms 5l, and means i?? QI" shifting or adjusting the arms. v

Y rlhe body 5l] ,may comprisegan elongate shank 55, and a" head 55 on the lower end 0f the shank. in the construction'illustrated the head 55 is rect 'l .v

in transverse cross section and is pro- Vith a fiat lower end. A stem 'or pilot 56 pro cts'. 'from the lower side of the head 55. A t 'nsvers'e opening 5l passesl through the head A c receive the `arms fil. The opening 5l is preferably' rectangular andhasiiat, smooth Walls. l/rnis 5| pass through the opening 5l of A,the he g55 land are arranged in side by side'rel l'Ivlile@grins 5| are rectangular o-r square transverse cross section andtheir fiat lsides -s denne ontlie other. The surfaces ofthe arms Elrideponthe Wallsqof the opening 5l (see Fig. 2).

rThe arms ,5ml :are 0f the same length and when egrtended are adapted to project a substantial disltancefirom the head 55.

A flhe'lcutting parts 52 are replaceably secured on the ,outer ends of the arms 5i. The active llovver vportionsof the cutting parts 52 are preferably narrow'to make a narrow annular cut in the Work. One cutting part 52 has Ya cuttingedge `5 8 for making the inner vvall of the annular cut While theol-.her cutting part 5 2 has a cutting edge 59'ffor" making the outer Wall of the cut. The Vcutting,I iarts SWZ'may be secured to the arms 5l fin'any suitable manner. Dove-tailed grooves 6Fl are show-n formed in the outer ends of the arms l5I L to *receive lthe correspondingly shaped cutting parts. Longitudinal Aslots llr continue inwardly from the grooves @il and transverse slots 62 are formed in the arms 5l adjacent the inner ends of the slots 6l. Clamp screws 63 are provided to clamp the split end portions of the arms 5l onto the cutting parts l2 to secure the cutting parts.

The means for simultaneously adjusting the arms 5| is a feature of the'invention. The means 53 includes sets of rack teeth 65 on the opposing inner sides of the arms 5l. The sets of teeth 65 are preferably of considerable length and are alike or identical. The teeth extend upwardly from the lower edges of the arms 5i and gradually die out before reaching the upper edgesY of the arms. While the teeth 65 may be of any selected shape, in the preferred construction; illustrated the teeth 65 are V-shaped in cross section.

The means 53 further includes an opening S6 in the lower end of the head 55 extending upwardly to the opening 5l. A pinion 6l' is adapted to be introduced into the opening `66 to cooperate with the sets of rack teeth 65. The pinion 61 is formed on the end of a stem 58 which in turn carries a suitable handle 69. As best illustrated in Fig. 2 of the drawing, the sets of rack teeth 65 are recessed in the inner sides of the arms 5|, leaving a space for the reception of the pinion 61'.- With the pinion 61 entered through the opening 66 to mesh with the rack teeth 65, rotation of the pinion serves to simultaneously adjust or shift the two arms 5| an equal distance.

Means is provided for setting or locking the arms 5| in the adjusted positions. includes a longitudinally extending recessed face 10 in the outer side of one of the arms 5|. A screw 1| is threaded through an opening in the wall of the head 55 and is adapted to engage the surface 10. When the screw 1| is tightened the two arms 5| are tightly clamped together in the opening 51 to be positively locked in their adjusted positions.

In the operation of the tool the screw 1| is loosened and the pinion 61 is introduced through the opening SI5 to mesh with the rack teeth 65. The pinion 1 is readily turned by means of its handle 69. Rotation of the pinion 61 in one direction simultaneously shifts the two arms 5| inwardly an equal distance and rotation of the pinion 61 in the other direction simultaneously moves the two arms 5I outwardly an equal extent. In this way the arms 5I may be easily and quickly adjusted to position the cutting parts 52 to make a cut of the required diameter. When the adjustment has been made the set screw 1| is tightened to secure the arms in the adjusted positions. A pilot bore is then formed in the work and with the shank 54 engaged in a drilling machine the pilot'56 is engaged in the pilot bore and the tool is rotated so that the cutting parts 52 make an annular cut in the work.

Having described only typical preferred form and application of my invention, I do not wish to be limited or restricted to the specific details herein set forth, but Wish to reserve to myself any variations or modifications that may appear to those skilled in the art or fall within the scope of the following claims.

Having described my invention, I claim:

1. A tool of the character described including a central elongate body, the body having a single transverse opening and an offset passage in it from its lower end communicating with the opening, overlapping arms shiftable in the opening and adapted to project laterally from opposite sides of the body, a central pilot projecting from the lower end of the body, cutting parts on the This means Y end offset from the pilot and which joins the transverse opening, a pair of arms shiftably engaged in the transverse opening in side by side relation to project from opposite sides of the body, cutting parts on the arms, sets of teeth on the -opposed sides of the arms, a pinion adapted to be entered in said longitudinal opening to cooperate with said teeth and rotatable to simultaneously shift the arms inwardly `and outwardly equal distances, and releasable means for holding the arms in the selected positions.

3. A tool of the character described including a body, the body with a central pilot projecting from its lower end and having a transverse opening and a longitudinal opening offset from the pilot and which joins the transverse opening, a pair of arms shiftably engaged in the transverse opening in side by side relation to project from opposite sides of the body, cutting parts on the arms, sets of teeth on the opposed sides of the arms, a key, a pinion formed on the key adapted to be entered in the longitudinal opening to cooperate with said teeth and then turned to shift the arms inwardly or outwardly, and releasable means for holding the arms in the selected positions.

4. A tool of the character described including a body having a transverse opening therethrough and a key opening connecting with the transverse opening from the lower end of the body, overlapping arms supported by the body with their outer ends projecting laterally from the body, the

`amounts to vary the distance between the body and the cutting parts, said means including a single rotatable actuating key insertable through the key .opening to engage the arms to impart movement thereto.

LAWSON A. SMITH. 

